Thanks all so far with the help in my initial steps with this project: rebuilding the carbs to get the bike running pre-stripdown, removal of the stuck rocker cover, knocking out the shock mounts from the swinging arm, removal of the steering races and identification of mystery parts along the way. The bike is now stripped down apart from the bottom end which Im intending to leave intact and, so far the wheels are still 'bearings in'. The first outside job of repainting the frame, swinging arm and various other brackets etc should start tomorrow.
Whilst Im waiting for the frame painting I am getting on with the head. All valves etc are out, the head is decarboned and Im now decarboning the valves pre to lapping them in. Whilst working on the inlet valve for #2 cyclinder I can see there is damage/an imperfection in the valve face (see picture). Should this valve be replaced with a new one and if so is it OK to replace one valve only? I have checked piston #2 and there is no sign of any impact damage on the piston. Also there is a single valve collet hiding somehwere on the floor of the shed which Im hoping to find but is so far proving elusive. Thanks, Mike